Insecticide treatment, film coating and rizobium soybean seed inoculationThe treatment of soybean seeds with chemical products to control pests may impair seed quality and the establishment of the rizobium-plant symbiosis. The aim of this work was to evaluate the performance of soybean seeds treated with insecticides and film coating, as well as the nodulation and plant growth. Soybean seeds were treated with insecticides and polymer in a 6x2 factorial scheme. The insecticides used in the treatments were carbosulfan, clotianidina, fipronil, imidacloprid, tiametoxan and a control without insecticides. Insecticides were applied with and without the polymer, as well as the control. Seeds were evaluated by the germination test, cold test and seedling emergence. In addition, they were inoculated with the strains BR86 and BR96, separately, and sowed in Leonard pots. During the flowering, the plants were evaluated using the number and dry matter of nodules and of the aerial part. The insecticide treatments can Recebido para publicação em abril de 2009 e aprovado em setembro de 2010 1 Parte da tese apresentada à Universidade Federal de Lavras pelo primeiro autor para obtenção do título de doutor.

Tratamento fungicida de sementes de soja inoculadas com Colletotrichum truncatum INTRODUÇÃOAs sementes são o principal veículo de transmissão de fungos fitopatogênicos de importância econômica na cultura da soja, os quais podem reduzir a sua germinação e o seu vigor (KRZYZANOWSKI & FRANÇA NETO, 2003) e originar focos primários de doenças (MACHADO, 2000). Dentre as doenças dessa cultura, a antracnose, agente causal Colletotrichum dematium var. truncata, compromete o desenvolvimento das vagens já em início de formação, podendo reduzir a qualidade fisiológica das sementes (HAMAWAKI et al., 2002;GALLI et al., 2007

Harvest of maize seeds with high moisture levels has been recommended; nevertheless, after harvest, the ears undergo the process of husking and there is a need to assess the compatibility of these processes. The purpose of this study was to assess the effects of mechanical husking on the quality of maize seeds collected at high moisture levels. Dent BM 3061 hybrid maize seeds, manually collected from the ear, with moisture contents of 45%, 40% and 35%, and a 20/64 round sieve were used. The ears were mechanically husked (CWA machine, 312 rpm), dried in a stationary drier at 35 ⁰C until reaching 22% moisture, followed by drying at 42 ºC until reaching 12%. Then, they underwent shelling, followed by a chemical treatment with Maxin® + K-obiol® + Actellic®. Seed quality was assessed according to the occurrence tests of mechanical damage, first count, germination, seedling emergence, emergence speed index, average emergence time, electrical conductivity, accelerated aging, cold test, and seed health test at every quarter for 9 months. The mechanical husking affects maize seed quality, depending on the degree of seed moisture at harvest and on the material studied. This hybrid's seeds can be collected with seed moisture levels at 40% with the use of mechanical husking.

Several factors affect the quality of soybean seeds, including the mineral nutrition of plants. Manganese (Mn) is an important nutrient because it has as one of its functions the enzyme activation. The aim of this study was to evaluate enzyme activity in seeds of soybean cultivars produced with foliar application of different doses of Mn. The experiment was conducted at the Universidade Federal de Lavras (UFLA) (Federal University of Lavras) in randomized blocks with three replications and 4 x 4 x 2 factorial arrangement consisting of four soybean cultivars, two conventional and its genetically modified RR derived (BRS Celeste and BRS Baliza RR; BRSGO Jataí and BRS Silvânia RR), four doses of Mn via foliar application (0; 200; 400 and 600 g Mn ha -1 ) and two stages of application (R 1 or R 3 ). In the seeds, the expressions of the enzymes esterase (EST), malate dehydrogenase (MDH), alcohol dehydrogenase (ADH), superoxide dismutase (SOD), peroxidase (PRX) and isocitratelyase (ICL) were determined. For evaluation of physiological quality, the germination test and emergence speed index (ESI) were performed. The Mn content in the seeds was also determined. The expression of the enzymes EST, SOD, PRX and ICL in soybean seeds are affected by foliar application of Mn, regardless of the stages of application. In the seeds of the cultivars that showed better physiological quality, Celeste and Baliza RR, greater expressions of the enzymes ADH and ICL and lower expressions of MDH and of PRX were observed.Index terms: Enzymes, Glycine max, quality, micronutrients. RESUMODiversos fatores afetam a qualidade das sementes de soja, dentre eles a nutrição mineral das plantas. O manganês (Mn) é um nutriente importante por ter como uma de suas funções a ativação enzimática. O objetivo, neste trabalho, foi avaliar a atividade enzimática em sementes de cultivares de soja, produzidas com aplicação foliar de diferentes doses de Mn. O experimento foi conduzido na Universidade Federal de Lavras (UFLA), em blocos casualizados, com três repetições e esquema fatorial 4 x 4 x 2, sendo quatro cultivares de soja, duas convencionais e suas derivadas transgênicas RR (BRS Celeste e BRS Baliza RR; BRSGO Jataí e BRS Silvânia RR), quatro doses de Mn via foliar (0; 200; 400 e 600 g Mn ha -1 ) e dois estádios de aplicação (R 1 ou R 3 ). Nas sementes, foram determinadas as expressões das enzimas esterase (EST), malato desidrogenase (MDH), álcool desidrogenase (ADH), superóxido dismutase (SOD), peroxidase (PRX) e isocitrato liase (ICL). Para avaliação da qualidade fisiológica foram realizados os testes de Germinação e de Índice de velocidade de emergência (IVE). Determinou-se, também, o teor de Mn nas sementes. A expressão das enzimas EST, SOD, PRX e ICL em sementes de soja são influenciadas pela aplicação de Mn via foliar, independente do estádio de aplicação. Nas sementes das cultivares, as quais apresentaram melhor qualidade fisiológica, Celeste e Baliza RR, foram constatadas maiores expressões das enzimas ADH e ICL e menores expressões de ...

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